Mayu is a normal girl from the urban area, and in the hours that she is not busy hunting Raimus, she stays at the computer playing several games, drawing and singing.
One day in the city where she lives, little monsters called Raimu began to appear, they are made concentrately of slime from: fire, water, plant and air. Due to the invasion of these little devils, a group of special agents was created by the government, trained to end these small beings, however, the population still did not understand what they were.
In one of these hunts, a fire Raimu ended up running away from one of these agents and ended up falling in the garden of Mayu's house, and she intuitively picked up and ate, thinking it was some kind of food. The agent seeing the scene was puzzled by the fact that nothing happened to her, and ended up taking her to speak to the head of the agency. There they hired her to end the invasion of these little demons, in return, she could consume the raimus at will.